When I had this issue with footloose:
- I went through the same steps mentioned by Bill
- I got this diagram from a mechanic - which really made me understand why you need to rev up initially when switching to reverse to get max torque over those diagonal groove which force the coupling - and then rev down to wherever you need...
- I still ended up getting a new Martec (my prior one had already been refurbished too many time).
Both helped for 5-10 years or so... but to be fair I am a bit fed up by this inherent folding prop limitation.
I am considering switching to a feathering prop (e.g.
https://www.pyiinc.com/max-prop-easy.html)... I saw in the forum that Ananda got one... and yes I read
https://www.yachtingmonthly.com/gear/folding-and-feathering-propeller-test-29807 :-)
I would like to know if you really loose that significantly when racing... I still love speed...